Electric vapor apparatus and method of operating the same.



- P. G. HEWITT.

ELECTRIC VAPOR APPARATUS AND METHOD OF OPERATING THE SAME. APPLICATIONFILED JAN. 11, 1906.

l 1 1%,545 Patented Sept. 15,, 1914..

TED STATS FATE PETER COOPER HEWITT, OF NEW YORK, N. Y., ASSIGNOR, BYMESNE ASSIGNMENTS, TO COOPER HEWITT ELECTRIC 00., OF HOBOKEN, NEWJERSEY, A CORPORATION or new JERSEY.

ELECTRIC VAPOR APPARATUS AND METHOD OF OPERATING THE SAME.

Speciiioation of Letters Patent.

Patented Sept. 15, 1914.

Application filed January 11, 1906. Serial m. 295,538.

tric apparatus when the said electrode is positive, as compared with theresistance of the same electrode when negative, has been pointed out byme and in various United States applications I have shown and describedmeans for utilizing this difference. Among other things, I havedescribed the negative electrode resistance to starting at an actingnegative electrode prior to the passage of a definite quantity ofcurrent, and the resistance residing at the same electrode after acertain definite quantity of current has begun to pass. I have designedvarious devices for the utilization of these phenomena in the arts;such, for example, as the well-known device for obtaining direct currentfrom an alternating current source through utilizing the negativeelectrode resistance to starting residing at an active positiveelectrode on a change of sign at such electrode. In other words, thequality residing in an electrode temporarily or normally acting as anegative electrode has been turned to a useful purpose, instead of beingmade to serve merely a an obstacle to the passage of current.

' I have found that a kindred phenomenon resides in the vapor betweenthe positive and negative electrodes of a vapor electric apparatus, orin the space intervening between any two electrodes. That is to say,there is a resistance to starting or a reluctance impeding the passageof current. residing in the vapor or the space intervening between twoelectrodes in a vapor apparatus.

The object of the present invention is to utilize this resistance orreluctance for the purpose of preventing short-circuiting between thenormal positive electrodes of such an apparatus. So far as I know, noprevious attempt has been made to render this resistance or reluctanceuseful for the purpose indicated. It is practicable, however,

. to utilize this phenomenon to prevent undesirable short circuiting inthe vapor apparatus and the object of the present invention is toprovide the necessary conditions under which the vapor column or thespace ntervening between positive electrodes may be utilized to preventinjurious short-circuiting.

Up to about six (6) inches or some other critical distance, the vapor orthe space intervening between positive electrodes apparently resentsonly a slight resistance to starting, ut this resistance becomesconsiderable when the critical distance is multiplied by two or more andat forty-eight (48) inches the vapor column may possess a resistance tostarting requiring a pressure of several thousand volts to start currentflowing.

The resistance to starting of the vapor column or space interveningbetween electrodes increases when the distance between electrodes isincreased, but in a far greater ratio. Another characteristic of thisresistance is. that it increaseswith the density of the intervening gasor vapor, whereas the negative electrode resistance to starting residingat any negative electrode, which re-' sistance is at present utilized inpreventing short-circuiting between electrodes in vapor converters,decreases with the increase of density of the intervening gas or vapor.

Taking as a type a vapor converter having two positive electrodes and acommon negative electrode, and assuming that the object at present incontemplation is that of preventing short-circuiting between positiveelectrodes, I may say that the present invention contemplates anapparatus in which the positive electrodes are located so far apart orthat the path between them shall be such as to prevent any probabilityunder ordinary or extraordinary conditions of operation of a dischargebetween the positive electrodes causing a destructive or injuriousshort-circuiting. It is, of course, understood that the length,diameter, density and characteristics of the vapor column from onepositive electrode to the other are the factors which determine thevoltage re uircd to cause a short-circuit, and this lengt and othercharacteristics may be so adjusted as to provide against all ordinary};1probabilities of shortcircuiting. It is possi by adjusting this lengthorthe distance between the positive electrodes to give to the vapor column between the positive electrodes a predetermined value as to thevoltage required to break dowri the resistance of the vapor two positiveelectrodes, by which arrangement the passage of current between eitherpositive electrode and the common negatlve electrode may be made to beara definite're-' lation as to the starting voltage required to thevoltage required for startlng a passage of current between the'twopositive electrodes. In this application, however, the relativelocation of the negative electrode is not necessarily taken intoaccount, the object being broadly to provide such a relation between thepositive electrodes as to obviate the danger of short-circuiting.Considering the disclosure herein, however, in a narrower sense, thedistance between the two positive electrodes being practically twicethat from either ositive electrode to the common negative el ectrode,the voltage required to cause a short-circuit between the two positiveelectrodes will be more than twice as great and may be more than fourtimes as great as that required for starting a current from eitherpositive electrode to the common negative electrode; and it seemsprobable that this ratio will more nearly approximate the cube of therelative distances rather than the square thereof, so that under ance ofthe vapor column as between the two positive electrodes will beapproximately eight times the breaking=down resistance be tween eitherpositive electrode and the common negative electrode. This statementrefers to the initial starting resistance of the vapor column itself. Tothis should be added the normal-negative electrode resistance of thepositive electrode which is for the moment a negative with relation tothe other positive electrode.

It will be understood that the structure containing two positiveelectrodes and a common negative electrode is simply taken as a type andthat the same inventive idea is easlly applicable to vapor converters orother vapor apparatus containing more than two positive electrodes. Itis also clear that the same principle of operation a plies to" otherforms of vapor apparatus besi es vapor converters.

It should further be understood that so far as the broad idea of thepresent invention is concerned, the positlve electrode need notbe'symmetrically placed with relation to the negative electrode, suchbroad idea being based upon the absolute separation of the positiveelectrodes from each other without regard to the'relative proportions ofthe difierent parts of the apparatus.

I have illustrated my invention in the accompanying drawing which is anelevation of a vapor device suited for the carrying out of my inventiontogetherwith a diagramof appropriate circuits connected therewith.

In the drawings, .1 is the container of a mercury vapor converter, and 2and 3 are extensions thereof which may be assumed to be of considerablelength, say, forty-eight (48) inches. Near the outer end of eachextension is an electrode, one being shown at 4, and another at 5. Atthe bottom of the container 1 is a main negative electrode, 6, common tothe two positive electrodes 4 and 5 and'in a separate pocket in the saidcontainer may be a supplemental positive electrode, 7,v separated fromthe main electrode 6 by an intervening ridge or bridge, 8. Theelectrodes 6 and 7 are usually of some conducting liquid such as mercuryand the starting of th apparatus is brought about in a manner nowwell-known, by tipping or tilting the apparatus so as to first bring theelectrodes 6 and 7 into contact and afterward to separate saidelectrodes so as to pro vide a local flow of current between theseelectrodes which local flow is. afterward transferred to the mainelectrodes through 'the intervening gas or vapor. Any other convenientstarting means may be employed in place of those described. Thisauxiliary starting electrode may be of any character and may or not beused as desired for in many "cases it'is not necessary.

certain conditions the breaking down resist- At 9 -I show the primary ofa transformer, the same being connected by conductors, 10

and 11, to a suitable alternating current gen .in any other suitablemanner, current will flow in a uniform direction through the apparatusand through the work circuit 14. By varying the length of the extensions2 and 3 the apparatus may be adapted for different voltages while anyincrease in thelength of these extensions will greatly increase thestarting resistance ofthe vapor path should there c any tendency foreither of the positive electrodes 4 or 5 temporarily to become anegative. ance of the vapor column, as already mentioned, is added thenatural negative elec- To the starting resisttrode resistance residingat each of the positive electrodes, when such electrodes becomesnegative.

I claim as myinvention v c 1. A rectifier for alternating currentincluding an exhausted container having anode chambers, an anode at theremoteend of each chamber and a cathode, the distance between any twoanodes by way of any possible current path greatly exceeding thatbetween either anode and the cathode.

2. A rectifier for-alternating currents including a hermetically sealedexhausted container having long and narrow spreading upwardly extendingtubular portions,

and a vaporizable cathode in the said container, together with solidanodes at the remote ends of the said tubular portions adapted forconnection to the terminals of an alternating current source whereby thestarting resistance of the said tubular portions is added to thenegative electrodes starting reluctance of the anodes.

Signed at New York, in the county of New York, and State of New York,this eighth day ofJanuary A; D. 1906.

PETER COOPER HEWITT.

Witnesses:

WMLH. CAPEL',

THOS. H. BROWN.

